Absorption refrigeration system



Aug. 5, 1941. H. L. LESCARBEAU ABSORPTION REFRIGERATION SYSTEM 5 Sheets-Sheet 1 Filed March 17, 1939 a w 0 WW 6 T) Ma 6 .l L n 4 o IF w V w 6 OJ 4m J j 5 a Attorneys Aug. 5, 1941.

H. L. LESCARBEAU ABSORPTION REFRIGERATION SYSTEM Filed March 17, 1939 5 Sheets-Sheet 2 Wm.,.,,,,,,,.,,,..,,.,,,.,,. ,mmumm I I I I I I I I I I I I I I I l I I I I I I I I I I I lllllllHllll lllllllHl HI I I llllllll :zrmunu Hllllllllllllll l/ fllllllllll Inventor Attorneys Aug. 5, 1941. H. L. LESCARBEAU ABSORPTION REFRIGERATION SYSTEM 5 Sheets-Sheet 5 Filed March 17, 1939 jiwd Inventor Attorneys eZTZ'eMQ/Zeazz By 7 a I Aug. 5, 1941.

H. L. LESCARBEAU ABSORPTION REFRIGERATION SYSTEM" Filed March 17, 1939 5 Sheets-Sheet 4 inventor idfiZIJldWZgdZZ v Attornys 1941. H. LESCARBEAU 2,251,746

ABSORPTION REFRIGERATION SYSTEM Filed March 17, 1939 5 Sheets-Sheet 5 Iriwentor 26 fli'acefjw 726016 By aa 3 Attorneys Patented Aug. 1941 UNITED STATES PATENT OFFICE 2,251,746 ABSORPTION REFRIGERATION SYSTEM Horace L. Lescarbeau, Montreal, Quebec, Canada Application March 17, 1939, Serial No. 262,425

2 Claims.

The present invention relates to improvements in absorption refrigeration systems.

An object of the invention is the provision of a refrigeration system of generally improved design.

Another object of the invetnion is the provision of a refrigeration system having increased efiiciency.

A further object of the invention is the provision of va'refrigeration system embodying improved absorption means.

Still another object of the invention is the provision of a refrigeration system having means for effecting improved circulation of a pressure equalizing fluid.

Other object and advantages of the invention will become apparent as the description progresses.

In the accompanying drawings forming a part of this specification and in which like reference sponding parts throughout the same:

Figure 1 is a more or less diagrammatic view of one form of apparatus embodying the invention,

Figure 2 is a longitudinal section through the generator thereof,

Figure 3 is an enlarged detail section through the rectifier,

Figure 4 is an enlarged section line 4-4 of Figure 1,

Figure 5 is an end view of the same,

Figure 6 is an enlarged transverse section taken on the line 6-6 of Figure 1,

Figure 7 is a similar section taken on the line 1-1 of Figure 1,

Figure 8 is a longitudinal section through the absorber of the apparatus,

Figure 9 is a section taken on the line 99 of Figure Figure 10 is a section taken on the line l0-HJ of Figure 8,

Figure 11 is an enlarged fragmentary section through the intermediate portion of Figure 8,

Figure 12 is an enlarged fragmentary detail elevation of a heat exchanger coil,

Figure 13 is a section along the line l3-l3 of Figure 12,

Figure 14 is an enlarged section taken on the line l4-l4 of Figure 13,

Figure 15 is an enlarged longitudinal section through a reservoir of the apparatus,

Figure 16 is an enlarged section taken on the line l6--l6 of Figure 1,

taken on the characters are employed to designate corre- Figure 17 is a diagrammatic view of another forni of the apparatus,

Figure 18 is a longitudinal generator thereof,

Figure 19 is a section taken on the line l9-l9 of Figure 18,'and

Figure 20 is a section taken on the line 20-20 of Figure 17.

Referring to a preferred embodiment of the invention illustrated at Figures 1 to 16 inclusive, designates a generator in the form of an elongated cylindrical shell arranged vertically and provided with a concentric flue 26 in the lower portion. This flue is adapted to receive an electric heating element 21 or other suitable heating means and extends from the bottom to a point above the middle section of the shell. In the upper portion of the shell 25 are mounted a plusection through the rality of inclined perforated baffles 28. A conduit 29 has communicative connection with the lower end portion of the shell and extends transversely therefrom. Another conduit 30 is wound in a coil about the exterior of the shell from the bottom portion to avpoint adjacent the top wherein the upper outlet of the conduit extends through an aperture in the shell into the interior.

Above the generator 25 is mounted a vertically disposed rectifier 32 in the form of a cylindrical tube provided with a plurality of baflles 33 within its exterior. A riser conduit 34 connects the generator with the rectifier, the lower end of the conduit making communicative connection with the central top head of the generator shell. while the upper-portion is bent to form a loop 35. The upper end of the conduit 34 connects with the lower portion of the tubular member 32 above the bottom end. A vertically disposed drain conduit 36, having the upper portion yprojecting through an aperture in the bOttOl'Ilrelld of the rectifier so that its upper open end terminates at a point above the connection of the conduit 34, extends downwardly and connects with the intermediate portion of the generator 25.

A condenser, in the form of a horizontally disposed coil 38, is mounted so that its inlet extension 39 connects with the upper end portion of the rectifier 32, while the bottom outlet extension conduit 40 extends horizontally to a vessel 4|. The coil 38 is preferably provided with heat transfer or cooling fins 42.

The vessel 4|, in the form of a cylindrical shell having exterior cooling fins 43, is arranged horizontally in a position approximately in alignment with the bottom extension of the coil 38. The outlet conduit 40 extends through one end of the with a vertically depending conduit 49 which connects with an absorber- 50 at an intermediate position. This absorber preferably embodies an interior cylindrical shell supported vertically and having the side wall corrugated and provided in the upper portion with a plurality of spaced horizontally extending trays 52 which are also of corrugated form. The interior of the shell 5| and the top surfaces of the trays 52 are lined with absorbent sheeting 53, of any preferred fibrous or other similar material, firmly held in position by wire screening 64. The shell 5| is mounted concentrically within and spaced from an exterior cooling jacket 55 having top and bottom conduit connections 56 and 51 which connect with a cooling coil 58. This construction is designed to provide eiilcient circulation of the cooling fluid between the shell and the jacket. The bottom of the conduit 46 connects with the top of the shell BI.

To the bottom of the absorber shell 5| is connected a pipe." extending downwardly therefrom and extended to form or connecting with a coil 6|. The outlet end of this coil connects with the lower end of the coiled conduit 30. The conduit 29 connects with an extension of relatively small bore disposed concentrically in spaced relation within the coil 6| and the pipe 60, separating from the latter at a point just belowthe absorber to assume an approximately U-shaped form 63 exteriorly of the absorber and connecting with the top of the absorber shell.

This extension 63 is formed so that a section 64 is coiled about the lower portion of the conduit 49 to provide a heat exchanger.

In operation,- the generator is adapted to contain a refrigerant, such as ammonia, in solution in an absorption fluid such as water which, upon being heated, expels the ammonia with some entrained absorption fluid. This vapor is conducted through the riser conduit 34 into the lower portion of the rectifier .vessel 32. Part of any water vapor is condensed in the riser conduit and flows back into the generator while fluid condensed in the rectifier collects in the bottom portion which provides an analyzer section or chamber. The

arrangement of the drain pipe 36 is such that liquid can accumulate in this analyzer to a predetermined level, above 'the level of the inlet of the conduit 34.

The practically pure ammonia vapor arising at the top of the rectifier passes through the connection 39 into and through the cooled coil 28 to be liquefied therein. Condensed ammonia passing from the condenser is conducted through the duct 40, which extends through the vessel 4|, and discharges therefrom in the outlet 45. The vessel 4| functions as a receiver or reservoir for an auxiliary inert fluid, functioning as a pressure equalizer, such as hydrogen gas which enters the inlet end of thevessel through the conduit 48. In the connection 45, which forms an outlet of the vesseland an inlet to the adjacent evaporator, theammonia evaporates in the presence of.

and difluses in the auxiliary gas to produce refrigeration, these mixed gases passing through the evaporator coil and downwardly through the conduit 49 to enter the mid-portion of the absorber shell above the liquid level therein. As shown at Figures 1 and ,8, the gases in the pipe 48 are conducted in heat exchange relation with the coil section 84 of the pipe employed to conduct weak solution liquor from the lower end of the generator into the top of the absorber. In consequence thereof, the relatively weak solution liquid falling through the absorber shell absorbs the ammonia, such absorption being fa-' cilitated by the fibrous material in the shell and on the trays, with the result that an enriched solution liquor accumulates in the bottom of the shell and is conducted therefrom by the pipe 60. While the ammonia is thus absorbed into the absorption liquor, the inert gas passes therefrom through the duct 48 and returns to the receiver generator above the level of the liquid therein where it .flows over the perforated baflles 28 to liberate refrigerant vapor.

The vapor conducted through the riser 34 from the generator is bubbled througli the liquid which accumulates in the bottom part of the rectifier vessel 32, eilecting analyzation and providing a substantially pure ammonia vapor in the upper part of the rectifier. The excess liquid from the lower part of this vessel is conducted into the generator, through the medium of pipe 36, at an intermediate point, between the relatively weak solution at the bottom and the strong solution in the upper part.

Within the absorbing chamber, the absorbent sheeting 53, together with the circulation of cooling fluid about the absorber shell, which may be an anti-freeze liquid, provides means for very efficient absorption of the refrigerant and its circulation through the primary circuit.

In another form of the apparatus, illustrated at Figures 17 to 20 inclusive, designed particularly for installations of smaller size, the generator embodies a cylindrical vertically elongated shell 66 provided with a flue 81 in the bottom. In the intermediate portion of the shell, just above its midsection, is provided a convex horizontal partition 69 dividing the shell into upper and lower chambers 10 and 1|. the latter having a plurality of baflies I2 therein. A conduit 13 extending vertically through the partition opens at a predetermined point in the upper chamber and is adapted to conduct liquid accumulating above this level into the lower chamber. A vapor takeand down into the upper chamber with its bottom open end disposed below the normal liquid level therein.

The vapor conduit 14 connects with the upper section of a condenser coil I1, while a pair of lower sections of the coil connect with the return pipe 16 providing an arcuate bifurcated loop 18 for effectively draining unvaporized fluid, mainly absorption liquid, from the upper part of the condenser. The auxiliary vapor conduit II is adapted to conduct any vapor in the upper chamber 10 into the condenser.

and preferably arranged in close proximity to narrow chamber at the rear of a refrigerator cabinet, so that the interior structure may be formed to extend the fulllength of the cabinet and materially increases the capacity thereof in proportion to the external dimensions, having in mind that no space would be required below the container body of the cabinet.

It will be obvious to those skilled in the art that many changes may be made in construction and arrangement of the system and the method without departing from the spirit of the invention and, therefore, the invention is not limited the conduit 40 from the condenser coil extending through the receiving vessel preferably maintains contact with the bottom of the shell and may advantageously be welded thereto. I

The tube 30 coiled about a substantial portion of the generator shell is also of'great utility in that it utilizes the excess heat from the generator heater to pump the rich liquor from the bottom of the absorber into the top of the generator chamber, thereby maintaining a high fluid level in the latter resulting in desired circulating pressure. The coiled conduit" may be welded to the exterior of the generator shell and, where greater pumping action would be useful, could be augmented by another coil arranged interiorly of the shell. This arrangement, together with the arrangement wherein the weak liquor from the bottom of the generator is conducted to the top of the absorber, provides effective circula-' to what is shown in the drawings and described in the specification but only as indicated in the annexed claims. i 1

' Having thus described my invention, I claim: 1. A generator for refrigerating apparatus comprising an elongated shell having a partition above its midsection dividing the shell into upper and lower chambers, aconduit disposed vertically in the shell extending through the partition to afford communication between the chambers, a conduit coiled about the exterior of the shell and having the upper end opening into the upper part of the lower chamber, a vapor outlet inthe upper part of the said lower chamber, a vapor outlet at the top of the upper chamber, and mean's'for heating the lower chamber of r the shell.

tion inasmuch as the weak absorption liquid flow- Such construction and assembly of the apparatus enables mounting the same in a relatively 2. In absorption refrigerating apparatus a generator, a condenser arranged at a level above the generator, a vertically elongated rectifier shell, a vapor conduit having communicative connection with the generator and connecting with the rectifier shell at a point in the lower portion above the bottom end, a drain conduit connecting with the generator and havingits upper portion projecting through the bottom of the rectifier, shell and its top end opening therein above the connection of the vapor conduit, and a conduit connecting the upper part of the rectal-- fler shell with the condenser.

HORACE L. LESCARBEAU. 

